The company reported a net loss of $59 million, or 2 cents per share, compared with net income of $227 million, or 10 cents a share a year earlier.

The most recent quarter's results include charges for share-based compensation and related payroll tax expenses and income-tax adjustments.

Excluding items, the company reported a profit of $311 million, or 12 cents per share.

Revenue increased 32 percent to $1.26 billion from $954 million a year ago.

Analysts had expected the company to report earnings excluding items of 11 cents a share on $1.23 billion in revenue, according to a consensus estimate from Thomson Reuters.

"We're still seeing stable and good growth," said Rick Summer, an analyst at Morningstar, on CNBC's "Closing Bell" after the release. "The question remains as to when we see that re-acceleration."

Advertising revenue shot up 36 percent to $1.09 billion, but revenue from its payments and other businesses increased just 13 percent to $176 million. Facebook CFO David Ebersman said the company's cost per ad grew 7 percent.

Its payments revenue fell 9 percent from the second quarter, driven by a decline in payments from social gaming company Zynga .

The company said it generated 14 percent of advertising revenue from mobile.

"People underestimate how good mobile is for Facebook," said CEO Mark Zuckerberg on the earnings call. "People on mobile use Facebook more often. We'll monetize better on mobile than on desktop."

Ebersman said the company's users grew 26 percent compared to the third quarter last year, and mobile users are increasing at an even faster pace.

The company also said its operating margin excluding items slid to 42 percent from 51 percent in the year-ago quarter.

Since Facebook's IPO in mid-May, its shares have shed about 50 percent from their $38 offering price, driven down by investors' concerns about how the company will be able to monetize its users' mobile usage.

In recent weeks, the company has launched several new products and features that could boost revenue growth including one that lets advertisers target users in real-time, based on outside websites they visit.

Because Facebook is the world's dominant social-networking company, the company's results are a gauge of the health of social media companies, as well as the overall online advertising environment.

Facebook's report comes days after online advertising rival Google prematurely delivered quarterly earnings and revenue that lagged analysts' estimates and reported a 15-percent decline in its average cost-per-click.